Weeds are problematic for many reasons. In home lawns, they choke out the grasses and overtake the landscape. In agriculture, they compete with crops for nutrients and cause a loss in yields.
Everyone from golf course superintendents to your average Joe deals with weeds on a daily basis. Even though lawn care professionals, farmers and backyard DIYers all vary in their professions, they all have one thing in common:
They use herbicides to deal with the problem.
We want to take a look at herbicides and answer common questions. Because there are so many different products on the market for weed control, we aim to break through the confusion and give a solid understanding of herbicides to our turf, ornamental, pest control and DIY audience.
The Types of Herbicides
Any time you hear the word "weed killer," it refers to an herbicide. It's a type of pesticide that is used solely to get rid of weeds in lawns, crops, gardens and landscaped areas. In general, there are two types to keep in mind:
Pre-Emergent Herbicides
These herbicides tackle weed problems below the ground and stop the plant from emerging from the soil. You might hear them called preventive herbicides as they prevent weeds from growing.
Post-Emergent Herbicides
These herbicides are used on actively growing weeds above the soil, preventing their continual growth and spread across the area. When it comes to post-emergent herbicides, it's important to pay attention to the type you're using. Use the wrong one, and it could spell trouble for the grass and other plants in the area.
Now let's talk about selective and non-selective herbicides. The difference between these two post-emergents is night and day.
Selective Herbicides
These herbicides contain certain ingredients that work on specific weeds at the target site. They only affect the processes that weeds need to develop and grow.Non-Selective Herbicides
These herbicides contain ingredients that kill most any plant they touch. That means these herbicides will destroy not only the weeds in the area but also the grass and other plants.
If you're targeting weeds but don't want to kill your zoysia, you'd use a selective herbicide. If you want to clear a plot of land and remove all the vegetation, a non-selective herbicide is your best bet.
You might also hear the term "broad-spectrum herbicide." This is a tricky one. It can refer to non-selective herbicides, or it can mean it targets a wide variety of weeds. It's best to read the label to make sure you know what you're using before you apply it to any weeds in the area.
We're not done yet. Now let's talk about systemic herbicides and contact herbicides.
Systemic Herbicides
These herbicides get absorbed into the plant and transported throughout its system. Because it moves through the weed, it kills the entire plant from the shoots to the roots.
Contact Herbicides
These herbicides are sprayed onto the plant and only affect the part of the weed that comes into contact with the active ingredient. Though the weed will die, the roots may survive and grow a new weed in the future.
As you can see, there's a lot more to herbicides than you'd think. Each one serves a unique purpose and can be beneficial or harmful depending on how you use it.
This brings up another point.
Read the Safety Labels!
We can't stress this enough. No matter if you're a seasoned farmer or just starting out in the lawn care profession, you MUST ALWAYS read the safety labels.
The safety label has more information on it than just how to protect yourself from the active chemicals.
It also tells you what it treats, where to use it, how to use it and what not to do. It tells you whether it's a broad-spectrum herbicide or a selective herbicide. It indicates what it kills and controls, how much to use and what to avoid if you don't want to kill beneficial plants in the area.
The label will also talk about timing. Can you apply it in the rain? How long before you can irrigate? What rate can you use for spurge?
If you don't read the labels, you're playing a risky game that can have detrimental effects on your lawn, crops or garden.
Types of Ingredients in Herbicides
There is a reason why there are so many herbicides on the market. One herbicide won't kill every weed. Some herbicides contain similar ingredients but may add more or less of the active ingredient. Pre-emergents use certain ingredients whereas post-emergents use others.
We'll provide a short list of the type of active ingredients commonly found in many of the herbicides we provide to our farmers, golf course superintendents, lawn care pros, ornamental markets and more:
- 2,4-D
- Chlorsulfuron
- Clopyralid
- Dicamba
- Diquat
- Glyphosate
- Imazapyr
- MCPP
- Metsulfuron-methyl
- Sulfentrazone
- Triclopyr
Like we said, this is a short, (extremely) short list of the types of active chemicals you'll find in herbicides.
One of the most common is 2,4-D. It's usually applied to the target weeds as an amine salt, but there are stronger ester types on the market. It's a systemic herbicide that targets many different broadleaf weeds but doesn't affect the surrounding grasses, turf or crops.
Another common, and also controversial herbicide, is glyphosate.
This ingredient is used in dozens and dozens of herbicides, including the popular Roundup ®. It's a non-selective, post-emergent chemical that is applied as a contact herbicide to kill weeds quickly.
As we've noted earlier, non-selective herbicides destroy all forms of plant life in the area. Any time you use glyphosate products, it's imperative that you read the safety label to prevent unnecessary harm to you and the surrounding landscape.
Which Herbicides Should You Use?
We talked to our trusted sales reps Rob Garcia and John Cabori about which herbicides they would recommend to you.
They're both very knowledgeable when it comes to herbicides. Even better, Rob provides herbicide information regarding Northern applications whereas John offers herbicide suggestions for the Southern market.
Rob Garcia - North
Gallery® (pre-emergent)
One of the best broadleaf herbicides available. This product is colorless and odorless and is very effective for dandelion control. Gallery can be applied in the spring or the fall and shows best performance when tan mixed with Barricade® or any prodiamine liquid which can be applied in the fall.
Strike 3® (post-emergent)
This is a great, all-around three-way herbicide. This product is cost-effective being an amine formulation and can be used in warmer weather where esters have greater potential for volatilization and off-site damage. With the addition of Quicksilver®, this will give fast action that is cost-effective.
Dimension® (pre-emergent)
Great pre-emergent for grass and broadleaf weeds. Timing is not as important as the product has control on early tiller stages, so if an application is missed due to weather, good control can still be achieved. Dimension also works well as a pre/post combination.
Tenacity® (post-emergent)
Has both broadleaf and grasses on the label. This product has very low use rates and gives a distinct color change to weeds that begin to die, which helps the customer access the weed control effects of the application. Tenacity is also able to be used on young seedlings so weed control applications can be made sooner after germination.
Horsepower® (post-emergent)
This non-2,4-D formulation is great in areas where there are restrictions on the number of applications of 2,4-D or in areas where you cannot use 2,4-D. This product is great for the harder to control weeds in lawns due to the high percentage of triclopyr in the formulation.
John Cabori - South
Tribute® Total (post-emergent)
Gets sedges, goose grass and several broadleaf weeds often found on athletic fields. Adding Turbulence or Atmos along with 21-0-0 soluble, can help control mature weeds such as dallisgrass. Caution label ideal for school IPM programs.
Celsius® (post-emergent)
Broadleaf weed control for LCO, golf and sport turf markets. Caution label ideal for school IPM programs. Can be applied to a variety of turf types. Strong on doveweed.
Drive® XLR8 (post-emergent)
Excellent choice for crabgrass control and a variety of difficult to control weeds in turf including torpedograss.
Monument® (post-emergent)
Gets sedges including kyllinga and several broadleaf weeds.
Certainty® (post-emergent)
Excellent on sedges, gets several broadleaf weeds, can be used on Bermuda as well as St. Augustine. Controls johnsongrass.
Avenue South
Can be applied to serveral turf types including St. Augustine.
Manuscript®
Finds its niche in controlling Tropical Signal Grass and Dallisgrass in Bermuda. This product comes with its own surfactant.
Pennant Magnum®
April is the best time to prevent Dove Weed. A timely application of Pennant Magnum from Syngenta can make a difference
Those are the Basics
We hope you learned a little more about herbicides in this blog and that the information can help you make more informed decisions about your herbicide selection. We at Heritage PPG are always here to answer your questions and available to help you decide which herbicides are right for your specific needs.